Thin film transistor liquid crystal displays (TFT-LCD) have characteristics of thin thickness, low power consumption, no radiation and the like. The TFT-LCDs have been developed in a fast pace and occupied a leading position of a current panel display market. Now, the TFT-LCDs have been applied widely in various products having a large, middle or small size which cover almost main electronic products of a nowadays information society. Application of the TFT-LCDs in products having large sizes includes application in liquid crystal televisions and high definition digital televisions.